1.8 billion people worldwide have no or only limited access to safe drinking water, severely impacting health, livelihoods and development. With global warming, this challenge will increase significantly. Traditional methods in rural communities of Africa and Asia involve boiling water over firewood, resulting in high CO2 emissions. HELIOZ has developed a simple and effective technology for creating safe drinking water: The solar-powered device WADI measures UV exposure of adjacent water bottles and thereby provides an innovative and simple method to use the sun to disinfect water. The product is patent-protected and its effectiveness was confirmed by WHO, with disinfection performance exceeding the harsh threshold of 99.99% in terms of water quality. Using WADI instead of the usual approach of boiling water reduces the carbon footprint. It can be transferred by HELIOZ into carbon credit certificates that customers can acquire for CO2 mitigation and CSR activities. HELIOZ is currently helping to purify 128 million litres of water/year and has reduced over 40’000 tons of CO2, establishing itself as an international player in the sustainability market.